Headboard



FIG. 1 is a left front perspective view of a headboard showing my new design;

FIG. 2 is a front elevational view thereof; and,

FIG. 3 is a side elevational view, the opposite side being a mirror image thereof.

The bottom and rear views of the headboard are not shown and form no part of the claimed design. The broken line showing of environmental elements is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a headboard, as shown and described. 